A thermal processing system is connected to a power source by a lead. Any of a number of leads having a variety of lead lengths can be disposed between the power source and the thermal processing system. Leads having multiple lengths can be provided and/or employed together with a thermal processing system. For example, a variety of lengths of leads are useful in, for example, a hand held thermal processing tool used around a large industrial work site or a hand held thermal processing tool employed in a contained work area, for example, in a studio or in a welding booth. The length of a lead attached to a thermal processing system (e.g., a torch, such as a plasma arc torch) can impact thermal processing system performance. The gas pressure provided to the thermal processing system can have an impact that is variously determined by the length of the lead. For example, where the thermal processing system is a plasma arc torch, the speed, cut quality, and the life of consumable parts in the plasma arc torch are impacted by the length of the lead that connects to the plasma arc torch.